Lens cleaning system



R. H. WAGER, JR

LENS CLEANING SYSTEM July 1, 1969 Sheet 1 0:2

Filed Oct. 21, 1965 m7 wzmcoawmm 29 2 :3. 4

3.5 2:24 mSmmm w on INVENTOR Robert H. Wager, Jr.

ATTORNEYS :5 5 22a mzmcoawwm 294 2529:

NFL

United States Patent 3,453,049 LENS CLEANING SYSTEM Robert H. Wager, Jr., South Orange, N.J., assignor to Robert H. Wager Co., llnc., South Orange, NJ., a corporation of New Jersey Filed Oct. 21, 1965, Ser. No. 499,877 Int. Cl. Gtllin 21/00 U.S. Cl. 356--73 4 Claims ABSTRACT OF THE DISCLOSURE A lens cleaning system for cleaning at least one of the lenses of an electro-optical smoke color and/or density measuring arrangement, characterized by the provision of means for directing against that side of a lens that is exposed to the smoke in a duct successive jets of pressure air, pressure air mixed with a cleaning liquid, and pressure air respectively.

This invention relates generally to improved cleaning means for cleaning the lens of an electro-optical system for measuring the physical characteristics of smoke, and more particularly to a lens cleaning arrangement for selectively directing successive jets of air and a mixture of air and a cleaning liquid against that side of a lens that is exposed to the smoke in a duct.

Arrangements for cleaning the lenses of electro-optical smoke indicating apparatus are generally known in the prior art, as evidenced by the patents in the name of Robert H. Wager Nos. 2,118,716 and 2,291,776. While these known systems have proven to be generally satisfactory, the various apparatus for measuring the characteristics of smoke have become so refined that the degree of cleanliness of the lenses of the electro-optical system is a major factor controlling the accuracy of measurement and the utility of the systems. For example, in the copending patent application Ser. No. 495,170, filed Oct. 12, 1965, in the names of Howard E. Kraus and Walter A. Smith, entitled Smoke Indicating Apparatus, now issued as U.S. Pat. No. 3,376,425, electro-optical system is disclosed for measuring both the intensity and color of the smoke in a duct, use being made of the quantity of the light trans mitted across the duct through the smoke to indicate intensity, and the quantity of light reflected by the smoke to indicate color. In this relatively refined system, clouding by the smoke of any of the lenses associated with the lamp unit, the transmitted light unit or the reflected light unit will adversely affect the accuracy of measurement.

The present invention was developed to avoid the drawbacks of the known lens cleaning systems and to provide an improved apparatus for directing successively against the surface of a lens exposed to smoke a blast of pressure air and a blast of a mixture of pressure air and a cleaning liquid, such as water. The system is operable first to direct a blast of pressure air against the lens to blow therefrom the loose soot and other impurities deposited thereon. A mixture of pressure air and a liquid is then directed against the lens to wash off the heavier residue that adheres to the glass. Finally, a follow-up blast of air alone is directed against the lens to clean and dry the same.

According to a more specific object of the invention, the cleaning system is designed to selectively clean the lenses associated with the lamp unit, the transmitted light unit and the reflected light unit, respectively, of an electrooptical smoke intensity and color measuring system. Owing to the selectivity of the lens cleaning operations, the

lenses of the various units may be cleaned in a desired practical order to obtain eflicient operation of the smoke measuring system in the shortest possible maintenance time. Consequently, since the transmitted light unit is normally near the observation location in maritime smoke indicating apparatus, it may be desired to clean the lens associated with this unit first to permit visual observation of the smoke.

According to a further object of the invention, pressure air is supplied from a source thereof to the lamp lens, the transmitted light lens, and the reflected light lens via first, second and third conduits controlled by first, second and third solenoid valves, respectively. Pressure liquid is supplied to the three lenses via fourth, fifth and sixth conduits controlled by fourth, fifth and sixth solenoid valves, respectively. Ganged selector switch means are provided for permitting energization of said fourth, fifth and sixth solenoid valves only when the first, second and third solenoid valves, respectively, are energized. Furthermore, push button switch means are provided for effecting energization of one of said first, second and third solenoid valves without energization of the corresponding fourth, fifth and sixth solenoid valves, respectively.

Other objects and advantages of the invention will become apparent from a study of the following specification when considered in conjunction with the accompanying drawing, in which:

FIGURE 1 is a schematic view illustrating the means for cleaning the lenses of an electro-optical system for measuring the intensity and color of smoke;

FIGURE 2 is a schematic diagram illustrating the electrical control circuit relative to the pressure air and pressure liquid supply means; and

FIGURE 3 is a detailed view illustrating the means by which pressure air, scavenging air and pressure liquid are directed against a lens.

Referring to FIGURE 1, the cleaning system is disclosed for cleaning the lenses 2, 4 and 6 of the lamp, transmitted light and reflected light units 8, 10 and 12, respectively, of an electro-optical smoke intensity and color measuring system similar to that disclosed in the aforementioned Kraus et al. patent application. The lamp unit 8 includes a lamp 14 for directing rays of light 15 through the lens 2 and into a boiler uptake duct 16 via the open-ended pipe 18 that extends through a wall opening in the duct. The light rays 19 transmitted across the duct enter a corresponding pipe 20, pass through lens 4 and are reflected by angularly arranged mirrors 22 and 24 to an observer 26. Arranged behind a transparent slit in mirror 22 are photocell means 28 that are connected with conventional light intensity measuring means (not shownl for indicating the density of the smoke in duct 16.

In the event that the smoke is white in color, at least a portion 31 of the lamp rays 15 are reflected by the smoke into an open-ended pipe 32 and through the lens 6 to other photocell means 34 that are connected with conventional light intensity measuring mean-s (not shown) for indicating the color of the smoke.

In accordance with the present invention, means are provided for directing one or more cleaning fluids against those surfaces of the lenses 2, 4 and 6 that are directly exposed to the smoke in duct 16. As shown in FIGURE 1, air under pressure (on the order :of to p.s.i.g.) is fed from source 40 to units 8, 10 and 12 via manifold 42 and conduits 44, 46 and 48 containing colenoid valves 50, 52 and 54, respectively. Similarly, pressure liquid (such as water under a pressure of approximately 50 to 70 p.s.i.g.) is supplied from source 60 to units 8, 10 and 12 via manifold 62 and conduits 64, 66 and 68 containing solenoid valves 70, 72 and 74, respectively. Finally, scavenging (i.e., cleaning) air is supplied to units 8, and 12 via conduits 76, 78 and 80 containing one-Way check valves 82, 84 and 86, respectively. Preferably each of the pipes 18, 20 and 32 is provided with damper or movable closure means 88 between the duct 16 and the corresponding lens.

Arranged adjacent the observer 26 is a push button control station 90 for selectively operating the solenoids to effect a desired cleaning of the various lenses. These control means include air and water push button switches 100 and 102 and a control knob 104 rotatable between positions A, B and C to efiect cleaning of lenses 4, 2 and 8, respectively. As shown in FIGURE 2, one stationary contact of push button switch 100 is connected with one side of the voltage source 106 by conductor 108. The other stationary contact of switch 100 is connected with the movable contact of air solenoid selector switch 110 having stationary contacts 112, 114, 116 connected with one end of the solenoid coils of solenoid valves 52, 50 and 54 via conductors 118, 120 and 122, respectively. The other ends of these solenoid coils are connected with the other terminal of source 106 via conductor 124. Furthermore, said other stationary contact of switch 100 is connected with a stationary contact of push button switch 102 via conductor 126. The other stationary contact of switch 102 is connected by conductor 130 with the movable contact of the water solenoid selector switch 132. As shown schematically in FIGURE 2, the movable contacts of selector switches 110 and 132 are ganged together for simultaneous movement by knob 104. The stationary contacts 134, 136 and 138 of switch 132 are connected by leads 104, 142 and 144 with one end of the solenoid coils of solenoid valves 72, 70 and 74. The other ends of these solenoid coils are connected with the voltage source via return 124.

Referring to the detailed illustration of FIGURE 3, the pressure liquid from conduit 68 is directed against the smoke-exposed side of lens 4 via nozzle means 170. Pressure air from conduit 46 is supplied to annular passage 172 contained in pipe 20 and outwardly against lens 4 via angularly arranged jet passages 174. Scavenging air is also supplied to annular chamber 172 via conduit 78 and one-way check valve 84. This check valve is designed to close to isolate scavenging air source from chamber 172 when the pressure of air in conduit 46 exceeds the pressure of scavenging air in conduit 78. Similar nozzle and jet passage means are provided for directing blasts of gaseous and liquid cleaning fluids upon the lenses associated with the lamp unit 8 and the reflected light unit 12.

Operation Assuming that the electro-optical smoke measuring system has been in use for a sufficiently long period of time to require cleaning of the lenses, knob 104 is adjusted to position A to eiiect initial cleaning of the lens 4 of the transmitted light unit 10, whereby the observer may visually inspectt the interior of the duct 16 by means of mirrors 24 and 22.

With push buttons 100 and 102 in the initial open position, scavenging air from duct 16 is directed against the three lenses 2, 4 and 6 via conduits 76, 78 and 80 and check valves 82, 84 and 86, respectively. Push button switch 100 is now closed for a given period of time (on the order of 15 to 20 seconds) whereby air solenoid 52 is energized from source 106 via conductor 108, switch 100, conductor 108, switch 110, conductor 118 and conductor 124. Pressure air is directed upon lens 4 to blow the heavier particles of soot and impurities therefrom. Since the pressure air in conduit 46 and chamber 172 exceed scavenging air pressure, check valve 84 is automatically closed to isolate chamber 172 from the scavenging air source.

Push button 100 is now released to de-energize solenoid valve 52 and to interrupt the pressure air blast upon lens 4. Check valve 84 again opens to resume the supply of the scavenging air upon the lens. In the event that the Water push button switch 102 should now be closed, there would be no operation of any solenoid valve since conductor 126 is de-energized by the open push button switch 100.

Assume now that both switches and 102 are closed, whereby solenoid valves 52 and 72 are opened to direct a mixture of pressure air and pressure water upon the lens 4, check valve 84 being automatically closed by the pressure air. The water push button switch 102 is closed only for a short period of time (1 to 2 seconds) to rinse from the lens the impurities that adhere thereto. Upon release of push button 102, water solenoid valve 72 is deenergized to discontinue the supply of cleaning fluid. Air push button switch 100 is maintained closed to direct a blast of drying pressure air against the lens. Upon release of bush button switch 100, low pressure scavenging air is again directed against the lens. If the lens 4 still appears dirty to the observer, the above process may be repeated as many times as necessary.

To clean the lens 2 associated with the lamp unit 8, knob 104 is rotated to position B, whereupon first the push button switch 100 is closed to direct pressure air against the lens, and then both switches 100 and 102 are closed to direct the mixture of liquid and air against the lens. Finally, switch 102 is opened and switch 100 is closed to direct drying air against the lens.

To clean lens 6 associated with the reflected light unit 12, knob 104 is rotated to position C and the above described lens cleaning operation is repeated.

While in accordance with the provisions of the Patent Statutes, the preferred form and embodiment of the invention has been illustrated and described, it will be apparent to those skilled in the art that changes may be made in the apparatus without deviating from the invention set forth in the following claims.

What is claimed is:

1. In an electro-optical system for measuring the characteristics of smoke in a duct and including at least one lens through which light is transmitted and one side of which is exposed to the smoke being measured, the invention which comprises first means for directing pressure air against said one side of said lens;

air supply means including a normally-deactivated air solenoid valve operable to supply pressure air to said first means;

air switch means coupled to said air solenoid valve to activate the same and thereby cause pressure air to be directed against said lens;

mixing means for mixing with said pressure air a cleaning liquid;

cleainng liquid supply means including a normally de-activated liquid solenoid valve operable to supply cleaning liquid to said second means; and

liquid switch means coupled to said liquid solenoid valve, said liquid switch means being operable to activate said liquid solenoid valve only when said first switch means is activated, thereby to cause a mixture of said air and cleaning liquid to be directed against said lens;

said air switch means, said air and liquid switch means,

and said air switch means being operable, in succession, to cause pressure air, .pressure air mixed with cleaning fluid, and pressure air, respectively, to be directed upon said lens.

2. Apparatus as defined in claim 1, and further comprising means including a one-way check valve for continuously supplying scavenging air to said lens, whereby when the air switch means is operated to activate said air solenoid valve, said check valve closes to isolate the scavenging air supply means from the lens.

3. Apparatus as defined in claim 1, wherein said system includes a plurality of said lenses each having associated therewith separate first means, air solenoid valve means, mixing means, and liquid solenoid valve means, respectively;

a voltage source, first selector switch means for selectively connecting each of said air solenoid valve means, respectively, in series with said air switch and said voltage source; and second selector switch means for selectively connecting one terminal of each of said liquid solenoid valve means with one terminal of said liquid switch, the other terminal of said liquid switch being connected with the selector contact of said first selector switch and the other terminals of said liquid solenoid valves being connected with said source in parallel with said air solenoid valves, whereby said liquid solenoid valves are energizable by said liquid switch only when said air switch is closed. 4. Apparatus as defined in claim 3, wherein said first and second selector switch means have ganged movable contacts.

References Cited UNITED STATES PATENTS McNeil et al.

Steinmetz 350-63 Wager.

Simon et al.

Longs 15-302 X Veit.

Hartridge.

Lafitte 350-63 X Stock et al. 134-l02 X Cropper et al.

Great Britain.

RONALD I. WIBERT, Primary Examiner.

WARREN A. SKLAR, Assistant Examiner.

US. Cl. X.R. 

